Processes and systems for transferring particulate substances from containers

ABSTRACT

Preferred processes are provided for unloading a particulate substance from a container using a cover system comprising a cover and a wand extending through the cover. The processes can include installing the cover system on the container so that the cover mates with the container and the wand extends into the particulate substance, connecting a pipe or a hose to the wand, and drawing the particulate substance through the wand and the pipe or hose.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.11/407,793 filed Apr. 19, 2006.

FIELD OF THE INVENTION

The present invention relates to the handling of particulate substancessuch as catalysts and additives used in fluid catalytic cracking (FCC)operations. More specifically, the invention relates to systems andprocesses that facilitate the transfer of particulate substances fromcontainers while the containers are covered.

BACKGROUND OF THE INVENTION

FCC units used to conduct FCC operations commonly include a circulatinginventory of bulk catalyst. The bulk catalyst is typically used toperform a primary function, such as producing naptha from petroleumfeedstock, the naptha being further processed into gasoline. Additives,which are often in the same fluidizable and particulated form as thecatalyst, are often introduced into the circulating inventory of bulkcatalyst to perform a secondary function such as reducing certain typesof emissions, e.g., SOx or NOx, produced by the FCC unit. Theseemissions are produced in the catalyst regenerator of the FCC unit wherecoke deposits from the cracked petroleum are burned off and theregenerated catalyst returned to the circulating catalyst inventory.These additives are usually introduced into the regenerator using aninjection device commonly referred to as a “loader.” Loaders are alsoused to add catalyst to the bulk inventory as additional catalystbecomes necessary due to factors such as attrition and deactivation.

For example, catalysts and additives are commonly transported instandard 55-gallon drums capable of holding approximately 300 pounds ofthe catalyst or additive. Tote bins capable of holding approximately2,000 pounds of catalyst or additive are another type of commonly-usedshipping container.

The containers used to ship catalyst or additive are usually coveredduring shipping to prevent contamination of the catalyst or additive byoxygen or moisture from the ambient environment. Covering the containersis also necessary to prevent fugitive emissions and other losses of thecatalyst or additive, and to reduce the potential for human contact withthe potentially toxic or caustic catalyst or additive.

The catalyst or additive can be unloaded from the shipping container toa silo or other suitable storage vessel at the refinery. The unloadingprocess is typically conducted by removing the cover of the container,and vacuuming the catalyst or additive. Removing the cover is necessaryto prevent a substantial pressure differential from developing betweenthe interior of the container and the ambient environment. A substantialpressure differential can potentially collapse or otherwise damage thecontainer.

Vacuuming the catalyst or additive while the cover of the container isremoved, however, exposes the catalyst or additive to the environment.Such exposure can be disadvantageous in applications where the contentsof the container are subject to contamination when exposed to theambient environment. For example, many catalysts and additives degradewhen exposed to moisture. Exposure to moisture can be particularlydisadvantageous when the catalyst or additive possesses hygroscopic,i.e., moisture absorbing, properties.

Moreover, particulate substances that possess pyrophoric, i.e., spark orflame inducing, properties can present a fire or explosion hazard whenexposed to or released into the ambient environment. Also, some types ofcatalysts and additives can degrade when exposed to the oxygen normallypresent in the ambient environment.

Consequently, an ongoing need exists for systems and methods that canfacilitate the unloading of particulate substances from containers whileminimizing or substantially eliminating exposure of the particulatesubstances to the ambient environment.

SUMMARY OF THE INVENTION

Preferred processes and cover systems are provided that permitparticulate substances to be unloaded from containers while thecontainers are covered.

Preferred processes are provided for unloading a particulate substancefrom a container using a cover system comprising a cover, a fittingattached to the cover, and a wand mounted on and in fluid communicationwith the fitting. The processes comprise installing the cover system onthe container so that the cover mates with the container and the wandextends into the particulate substance, connecting a pipe or a hose tothe fitting, and drawing the particulate substance through the wand, thefitting, and the pipe or hose.

Preferred processes for transferring catalyst and/or additive from acontainer to an injection device that injects the catalyst and/oradditive into a fluid catalytic cracking unit comprise installing acover on the container; inserting a wand into the catalyst and/oradditive; placing the wand in fluid communication with a vacuum sourceof the injection device; and drawing the catalyst and/or additive fromthe container by way of the wand.

Preferred processes for transferring a particulate substance from acontainer to an injection device capable of injecting the particulatesubstance into a fluid stream comprise installing a cover on thecontainer, and vacuuming the particulate substance through the cover andinto the injection device.

Preferred cover systems for a container comprise a cover that mates withthe container, a wand capable of being inserted through a hole formed inthe cover, and a cradle for holding the container in a tiltedorientation.

Preferred systems for introducing catalyst and/or additive into a fluidcatalytic cracking unit comprise an injection device comprising a vacuumsource and a chamber. The chamber is in fluid communication with thevacuum source, receives the catalyst and/or additive, and is capable ofbeing pressurized to inject the catalyst and/or additive into the fluidcatalytic cracking unit.

The systems also comprise a container defining a volume that holds thecatalyst and/or additive, and a cover system. The cover system comprisesa cover capable of mating with the container and further defining thevolume, and a wand capable of extending through the cover and into thevolume so that the wand is inserted in the catalyst and/or additive. Thewand is in fluid communication with the vacuum source so that thecatalyst and/or additive is drawn through the cover and into theinjection device in response to a vacuum generated by the vacuum source.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description ofa preferred embodiment, are better understood when read in conjunctionwith the appended diagrammatic drawings. For the purpose of illustratingthe invention, the drawings show an embodiment that is presentlypreferred. The invention is not limited, however, to the specificinstrumentalities disclosed in the drawings. In the drawings:

FIG. 1 is a side cutaway view of a preferred cover system installed on abarrel, with the barrel supported in a tilted orientation by a cradle;

FIG. 2 is a top perspective view of the cover system and the barrelshown in FIG. 1, depicting a hose being mated with a fitting of thecover system;

FIG. 3 is a top perspective view of the cover system and the barrelshown in FIGS. 1 and 2, depicting the cover system being lowered ontothe barrel;

FIG. 4 is a top perspective view of the cover system and the barrelshown in FIGS. 1-3, depicting the cover system being secured to thebarrel;

FIG. 5 is a top perspective view of the cover system and the barrelshown in FIGS. 1-4, depicting the cover system fully installed on thebarrel;

FIG. 6 is a top view of a cover of the cover system shown in FIGS. 1-5;

FIG. 7 is a side view of a wand of the cover system shown in FIGS. 1-6;

FIG. 8A is a side view of a vacuum relief mechanism of the cover systemshown in FIGS. 1-7;

FIG. 8B is a front view of the vacuum relief mechanism shown in FIG. 8A;

FIG. 9 is a cross-sectional side view of a loader that can vacuum aparticulate substance from the barrel by way of the cover system shownin FIGS. 1-8A, and inject the particulate substance into an FCC unit;

FIG. 10A is a side view of an alternative embodiment of the cover systemshown in FIGS. 1-8, depicting a wand of the cover system about to piercea membrane of the cover system; and

FIG. 10B is a side view of the cover system shown in FIG. 10A, depictingthe wand after the wand has pierced the membrane.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIGS. 1-8B depict a preferred cover system 10 for a container such as adrum 12. The cover system 10 can facilitate the transfer of aparticulate substance from the drum 12. The drum 12 can be, for example,a standard 55-gallon drum. The particulate substance can be, forexample, catalyst and/or additive 11 for use in an FCC unit (not shown).The catalyst and/or additive is depicted in FIG. 1 by the referencecharacter 11.

The use of the cover system 10 in connection with the drum 12 isdisclosed for exemplary purpose only. Alternative embodiments of thecover system 10 can be used with other types of containers, includingtote bins, square or rectangular containers, and other types ofcontainers having shapes and sizes different than those of a 55-gallondrum. Moreover, the cover system 10 can be used to facilitate thetransfer of particulate substances other than catalysts and additives.

The cover system 10 comprises a cover 14 configured to mate with thedrum 12. The cover 14 and the interior of the drum 12 define an internalvolume 25, as shown in FIG. 1. The cover system 10 allows the internalvolume 25 to be placed in fluid communication with a vacuum source, suchas an injection device in the form of a loader 102 depicted in FIG. 9.The vacuum generated by the loader 102 can draw the catalyst and/oradditive 11 from the drum 12 and into the loader 102. The loader 102 canthen inject the catalyst and/or additive 11 into a regenerator of theFCC unit.

The loader 102 comprises a dust collector 116 and a transfer pot 118.The transfer pot 118 adjoins the dust collector 116, and is in fluidcommunication with the regenerator of the FCC unit on a selective basis.The loader 102 also comprises a vacuum producer 130 in fluidcommunication with the dust collector 116.

The dust collector 116 defines an internal volume 126. The dustcollector 116 includes three pipe guides 140 that extend from a wall ofthe dust collector 116 and into the internal volume 126.

The internal volume 126 can be placed in fluid communication with threeof the drums 12 by hoses 138 or other suitable means such as hardpiping. Each hose 138 can be connected to the dust collector 116 by wayof an associated valve 142 mounted on the dust collector 116. The innerdiameter of each hose 138 is preferably approximately one toapproximately five inches. More preferably, the inner diameter of eachhose 138 is approximately two to approximately three inches. Preferredvalues for the inner diameter of the hoses 138 are presented forexemplary purpose only; the diameter of the hoses 138 can lie outside ofthe noted ranges.

Each pipe guide 140 is connected to an associated one of the valves 142.The valves 142 permit the associated hoses 138 and drums 12 to beisolated from the internal volume 126 on a selective basis. An internalor external manifold (not shown) can be used in lieu of the threeseparate valves 142 in alternative embodiments of the loader 102.Moreover, alternative embodiments of the loader 102 can be equipped withmore or less than three valves 142 and three pipe guides 140.

The vacuum producer 130 generates a vacuum within the internal volume126 of the dust collector 116. The vacuum draws the catalyst and/oradditive 11 from one of the drums 12 when the associated valve 142 isopen to permit the internal volume 126 to communicate with the drum 12.

The catalyst and/or additive 11 is discharged into the internal volume126 of the dust collector 116 by the corresponding pipe guide 140 afterpassing through the associated hose 138 and valve 142. The path of thecatalyst and/or additive 11 is denoted in FIG. 9 by arrows 143. Thecatalyst and/or additive 11 falls to the bottom of the dust collector116 and into the transfer pot 118. The transfer pot 118 is subsequentlypressurized, and the catalyst and/or additive 11 is injected into theregenerator of the FCC unit in response to the pressure within thetransfer pot 118.

The operation of the loader 10, including opening and closing of thevalves 142, pressurization of the transfer pot 118, generation of thevacuum in the dust collector 116, etc., can be controlled automaticallyby an electronic controller (not shown) of the loader 102.

Further details of a loader suitable for use as the loader 102 areincluded in U.S. application Ser. No. 10/806,563, filed Mar. 23, 2004,the contents of which is incorporated by reference herein in itsentirety.

The preceding details of the loader 102 are presented for exemplarypurposes only. The cover system 10 can be used to facilitate thetransfer of particulate substances to systems and devices other than theloader 102. For example, the cover system 10 can be used to facilitatethe transfer of particulate substances to delivery vehicles, reactorunits, mixers, or storage containers. Moreover, the cover system 10 canbe used to facilitate the transfer of particulate substances to loadersthat can be connected to no more than one of the drums 12 at any onetime.

The cover 14 of the cover system 10 is configured to securely mate withthe drum 12. In particular, the cover 14 has a lip 20 that engages a rim22 formed around the upper edge of the drum 12. The lip 20 and the rim22 are depicted in FIGS. 3 and 6. The cover system 10 can include acompression ring 18 that engages the lip 20 and the rim 22. Thecompression ring 18 can be tightened around the lip 20 and the rim 22 bya fastener or other suitable means that draws opposing ends of thecompression ring 18 together. The compression ring 18, when tightened,drives the lip 20 and the ring 22 together, thereby securing the cover14 to the drum 12 and substantially sealing the interface between thecover 14 and the drum 12.

The use of the compression ring 18 to secure the cover 14 to the drum 12is disclosed for exemplary purposes only. Other types of securing means,such as fasteners or clamps, can be used in the alternative.

The cover system 10 includes features that permit the catalyst and/oradditive 11 to be drawn out of the drum 12 while the cover 14 isinstalled on the drum 12. In particular, the cover 14 has a firstpenetration point or opening 26 formed therein. The first opening 26 ispreferably located proximate an outer perimeter of the cover 14, asshown in FIG. 6.

The system 10 further includes a fitting 28 having a first end 28 a anda second end 28 b, as shown in FIG. 1. The fitting 28 has a flow pathdefined therein and extending between the first and second ends 28 a, 28b. The diameter of the flow path can be approximately two inches. Theoptimal value for the diameter of the flow path is applicationdependent, and can vary with factors such as the maximum desired rate atwhich the catalyst and/or additive 11 is to be unloaded from the drum12; a specific value for the diameter is disclosed for exemplarypurposes only.

The fitting 28 is attached to the cover 14 so that the fitting 28extends through the port 26, and a portion of the fitting 28 projectsdownward into the volume 25 when the cover 14 is mounted on the drum 12.The first end 28 a of the fitting 28 is located within the volume 25,and the second end 28 b is accessible from the exterior of the drum 12and the cover 14 when the cover 14 is mated with the drum 12.

The fitting 28 can be attached to the cover 14 using threaded rings 30that engage complementary threads formed on the fitting 28 as shown, forexample, in FIG. 1. Gaskets (not shown) or other suitable means can beused to seal the interface between the rings 30, the cover 14, and thefitting 28. Other permanent, semi-permanent, and non-permanent means forsecuring the fitting 28 to the cover 14 can be used in the alternative;for example, a plastic insert that securely engages the fitting 28 andthe periphery of the first opening 26 can be used in lieu of thethreaded rings 30.

The fitting 28 is depicted as substantially elbow-shaped for exemplarypurposes only. Fitting having other shapes, including substantiallystraight fittings, can be used in the alternative.

The system 10 can also include a wand 33 formed from a length of tubing,as shown in FIGS. 1 and 7. A first end 33 a of the wand 33 can beconnected to a first end of a nipple 35 (depicted in FIG. 7) by asuitable means such as clamps or threads (not shown). A second end ofthe nipple 35 can be connected to the fitting 28 by a suitable meanssuch as clamps or threads, so that the wand 33 is in fluid communicationwith the fitting 28. The wand 33 can be connected to the fitting 28using other means in alternative embodiments. The wand 33 can beconnected directly to the fitting 28 in other alternative embodiments.

The inner diameter of the wand 33 can be approximately two inches. Theoptimal value for the inner diameter of the wand 33 is applicationdependent, and can vary with factors such as the maximum desired rate atwhich the catalyst and/or additive 11 is to be unloaded from the drum12; a specific value for the inner diameter is disclosed for exemplarypurposes only.

The length of the wand 33 is preferably chosen so that a second end 33 bof the wand 33 is located proximate a bottom surface 12 a of the drum 12when the cover 14 is installed on the drum 12, as shown in FIG. 1.Preferably, the lowermost point of second end 33 b is located not morethat approximately one-half inch from the bottom surface 12 a when thecover 14 is installed on the drum 12.

The second end 33 b of the wand 33 is preferably angled in relation tothe longitudinal axis of the wand 33, as depicted in FIGS. 1 and 7. Thisfeature can increase the effective area through which the catalystand/or additive 11 is drawn into the wand 33. Moreover, it is believedthat the angled orientation of the second end 33 b in relation to thebottom surface 12 a of the drum 12 can minimize the potential for theopening defined by the second end 33 b to become plugged with thecatalyst and/or additive 11. Also, the angled orientation of the secondend 33 b is believed to reduce the potential for a vacuum lock to formbetween the second end 33 b and the bottom surface 12 a.

One or more holes are preferably formed in the wand 33, proximate thefirst end 33 a. Most preferably, four circular holes 34 are formed inthe wand 33 at equally-spaced angular positions around the circumferenceof the wand 33, as shown in FIGS. 1 and 7. Each of the holes 34preferably has a diameter of approximately 0.25 inch (6.4 mm), and ispreferably located approximately 0.75 inch (19.1 mm) from the cover 14when the wand 33 is installed on the cover 14. The holes 34, it isbelieved, can act as vacuum relief ports that further reduce thepotential for a vacuum lock to form between the second end 33 b of thewand 33 and the bottom surface 12 a of the drum 12.

Specific values for the diameter of the holes 34, and for relativepositions of the holes 34 on the wand 33 are presented for exemplarypurposes only; the holes 34 can be sized and positioned differently inalternative embodiments. Moreover, the holes 34 can have a shape otherthan circular in alternative embodiments.

The fitting 28 can mate with an associated one of the hoses 138 usingclamps, couplings, or other suitable means. As discussed above, the hose138 can be connected to an associated valve 142 of the loader 102. Thehose 138, fitting 28, and wand 33 thus place the internal volume 126 ofthe dust collector 116 in fluid communication with the volume 25 definedby the drum 12 and the cover 14.

The use of the hose 138 to place the volume 25 in fluid communicationwith the loader 102 is disclosed for exemplary purposes only. Othersuitable conveying means, such as hard piping, can be used in thealternative. Moreover, multiple lengths of hose connected by fittings orother suitable means can be used in lieu of the single hose 138.

Alternative embodiments of the cover system 10 can include a membrane 61of sealable material, as shown in FIGS. 10A and 10B. The membrane 61 canbe secured to the cover 14 so that the membrane 61 spans the opening 26.The sealable material of the membrane 61 can be pierced by the secondend 33 b of the wand 33 as the wand 33 is inserted through the opening26 after the cover 14 has been placed on the drum 12, as denoted by thearrows 65 in FIGS. 10A and 10B. The sealable material is sufficientlyresilient, malleable, and/or controllable to create a seal between theouter circumference of the wand 33 and the remaining portion of themembrane 61. The use of the membrane 61 can obviate the need to securethe fitting 28 to the cover 14 using the rings 30.

The system 10 preferably includes a vacuum relief mechanism 40. Thevacuum relief mechanism 40 can be attached to a fitting 41. The fitting41 can extend through a second penetration point or opening 42 formed inthe cover 14 and shown in FIG. 6, so that the vacuum relief mechanism 40is in fluid communication with the volume 25 by way of the fitting 41.

The fitting 41 can be secured to the cover 14 using a suitable meanssuch as threaded rings 44 that engage complementary threads formed onthe fitting 41 as shown, for example, in FIG. 1. Gaskets (not shown) orother suitable means can be used to seal the interface between the rings44, the cover 14, and the fitting 41. Other means for securing thefitting 41 to the cover 14 can be used in the alternative, including,for example, a plastic inset that securely engages the fitting 41 andthe periphery of the second opening 42.

The vacuum relief mechanism 40 can include, for example, a housing 47and a fitting 59 attached to the housing, as shown in FIGS. 8A and 8B.The housing 47 has an internal passage 49 formed therein. The fitting 59includes a screen 45. The fitting 59 is positioned on the housing 47 sothat the screen 45 spans one end of passage 49. The screen 45 can be,for example, a 40-mesh screen; screens having a mesh other than 40 canbe used in the alternative.

A first end of the housing 47 is connected to the fitting 41 by asuitable means such as threads, so that the passage 49 is in fluidcommunication with the internal volume 25 of the drum 12. An elbow 55can be connected to the second end of the housing 47. The elbow 55 facesdownward, to discourage the influx of contaminates such as rain throughthe vacuum relief mechanism 40.

The screen 45 permits air from the ambient environment to enter theinternal volume 25 by way of the passage 49 and the fitting 41, whilepreventing the influx of foreign matter such as leaves, rodents, etc.The vacuum relief mechanism 40 thus acts as a vacuum breaker that canhelp to ensure that the pressure differential between the internalvolume 25 and the ambient environment does not exceed the structurallimits of the drum 12 or the cover 14.

The use of a vacuum relief mechanism 40 employing a screen is disclosedfor exemplary purposes only. Other types of vacuum relief mechanisms canbe used in the alternative.

The fitting 41 is preferably configured to accommodate a vacuum gauge 46that provides an indication of the vacuum within the volume 25 as thedrum 12 is being unloaded. The vacuum gauge is depicted in FIGS. 1-5.

The fitting 41 can also be configured to accommodate a pressure reliefvalve 51 shown in FIGS. 1-5. The fitting 41 can be a T-shaped fittingthat places each of the vacuum gauge 46, the pressure relief valve 51,and the vacuum relief mechanism 40 in fluid communication with theinternal volume 25. A first end of the pressure relief valve 51 can beconnected to the fitting 41 by a suitable means such as threads. Anelbow 63 can be connected to a second end of the pressure relief valve51, to discourage the influx of contaminates such as rain.

The pressure relief valve 51 can relieve the pressure within theinternal volume 25 when the pressure within the internal volume exceedsthe pressure of the ambient air by a predetermined amount. Thissituation can occur, for example, when the drum 12 inadvertentlypressurized, or when the catalyst and/or additive 11 within the drum 12becomes heated, causing evaporation of volatiles from the catalystand/or additive 11. A pressure relief valve suitable for use as thepressure relief valve 51 can be obtained, for example, from Circle SealControls, Inc., of Corona, Calif. as the 500 Series Adjustable Popoff &Inline Relief Valve.

Alternative embodiments of the cover system 10 can be configured withoutthe vacuum relief mechanism 40, the vacuum gauge 46, and/or the pressurerelief valve 51.

The use of a T-shaped fitting 41 to accommodate the vacuum gauge 46, thepressure relief valve 51, and the vacuum relief mechanism 40 isdisclosed for exemplary purposes only. Other types of fittings can beused in the alternative. Moreover, each of the vacuum gauge 46, thepressure relief valve 51, and the vacuum relief mechanism 40 can beaccommodated by its own individual fitting mounted on the cover 14, inalternative embodiments.

The internal volume 25 can be placed in fluid communication with asource of a gas, such as nitrogen, that will not react with the catalystand/or additive 11. This feature can permit the volume 25 to be filledwith a blanket of nitrogen gas as the catalyst and/or additive 11 isdrawn out of the drum 12. The connection with the source of nitrogen gascan be facilitated by, for example, a fitting 53 mounted on the cover14, and a length of hose 139 connected to the fitting 41 as depicted inFIGS. 1-5. The fitting 53 can extend through the cover 14 by way of aport or opening 57 formed therein; the opening 57 is depicted in FIG. 6.Alternative embodiments of the cover system 10 can be configured withoutthe fitting 53 and the hose 139.

The system 10 preferably includes a means for supporting the drum 12 ina tilted orientation as the drum 12 is unloaded. For example, the system10 can include a cradle 50, depicted in FIG. 1. The cradle 50 ispreferably configured so that a longitudinal or central axis “C1” of thedrum 12 is angled less than approximately ninety degrees in relation tothe vertical direction when the drum 12 is positioned on the cradle 50.More preferably, the cradle 50 is configured so that the longitudinalaxis C1 is angled between approximately twenty to approximately sixtydegrees in relation to the vertical direction.

Tilting the drum 12 can help ensure that a substantial entirety of thecatalyst and/or additive 11 is drawn out of the drum 12. Moreparticularly, the drum 12 is preferably positioned on the cradle 50 sothat the second end 33 b of the wand 33 is located at approximately the6:00 o'clock position, when viewed from a perspective rotated ninetydegrees from the perspective of FIG. 1. Moreover, the first opening 26is located proximate the outer perimeter of the cover 14, as notedpreviously. This feature helps to position the second end 33 b of thewand 33 proximate the lowest point of the drum 12 when the drum 12 isoriented as noted.

The tilted orientation of the drum 12 causes the catalyst and/oradditive 11 in the drum 12 to be drawn toward the lowest point of thedrum 12 by gravity as the drum 12 is emptied. Positioning the second endof the wand 33 b proximate the lowest point of the drum 12 can thus helpto ensure that a maximal amount of the catalyst and/or additive 11 isdrawn out of the drum 12.

The use of the cradle 50 to support the drum 12 in a tilted orientationis disclosed for exemplary purposes only. Other means for tilting thedrum 12 can be used in the alternative. For example, the drum 12 can beplaced on a ramp having an inclined surface. As a further example, thedrum 12 can be placed on a hand-truck or other carrying device and heldin a tilted orientation during the unloading process.

The drum 12 can be used to hold the catalyst and/or additive 11 duringtransport to the refinery or other point of use, i.e., the drum 12 canbe used as a shipping container. The drum 12 can also be used to storethe catalyst and/or additive 11 at the refinery or other point of useuntil the catalyst and/or additive 11 is needed. A conventional covercan be installed on the drum 12 during shipping and storage.

The drum 12 can be moved to a location at which the hose 138 can beconnected to the fitting 28. Alternatively, the hose 138 can beconnected to the drum 12 where the drum 12 is stored, thereby obviatingthe need to move the drum 12 from the storage area.

The cover used for shipping and storage can be removed from the drum 12.The cover 14, with the fining 28, wand 33, vacuum relief mechanism 40,fitting 41, pressure relief valve 51, and vacuum gauge 46 mountedthereon, can then be installed as depicted, for example, in FIGS. 2-5.The cover 12 can be moved with a side to side or circular motion helpdrive the wand 33 downward into the catalyst and/or additive 11.

In alternative embodiments equipped with the membrane 61 of sealablematerial, the wand 33 can be inserted through the membrane 61 and intothe catalyst and/or additive 11 after the cover 14 has been placed onthe drum 12. The sealable material, a discussed above, is pierced by thewand 33, and forms a seal around the outer circumference of the wand 33.

The compression ring 18 can be installed once the cover 14 has beenplaced on the drum 12. The compression ring 18 can be tightened to drivethe lip 20 of the cover 14 and the ring 22 of the drum 12 together,substantially sealing the interface between the cover 14 and the drum12. The hose 138 can be connected to the fitting 28, to place theinternal volume 25 in fluid communication with the loader 102. The hose139 can be connected to the fitting 53 to place the internal volume 25in fluid communication with the source of nitrogen, if the cover system10 is configured to provide a nitrogen blanket within the internalvolume 25 during the unloading process.

The drum 12 is preferably placed on the cradle 50 or other supportingmeans after the cover system 10 has been installed, to help minimize thepossibility of spillage of the catalyst and/or additive 11 during theinstallation process.

The hose 138, as discussed above, is in fluid communication with avacuum source, such as the dust collector 116 of the loader 102, on aselective basis. The valve 142 of the loader 102 can be opened when theelectronic controller of the loader 102 determines that the injectionsequence for the particular catalyst and/or additive 11 in the drum 12is to commence. The vacuum within the dust collector 116 draws theparticulate substance from the drum 12 by way of the hose 138, fitting28, and wand 33. The path of travel of the catalyst and/or additive 11is denoted by the arrows 143 in FIGS. 1 and 9.

The fitting 53 and the hose 139 allow the nitrogen gas to be drawn intothe volume 25 within the drum 12 as the catalyst and/or additive 11 isremoved. The path of travel of the nitrogen gas is denoted by the arrows147 in FIG. 1. Replacing the catalyst and/or additive 11 with a blanketof nitrogen gas can reduce the potential for contamination of thecatalyst and/or additive 11, particularly in applications where theentire amount of the catalyst and/or additive 11 in the drum 12 is nottransferred to the loader 102 in a single operation, i.e., where some ofthe catalyst and/or additive 11 remains in the drum 12 for transfer at alater time.

One, or more than one of the drums 12 can be connected to the loader 102at one time, as discussed above. If desired, three cover systems 10 canbe installed on three drums 12 that each hold a different type ofcatalyst and/or additive 11. The catalyst and/or additive 11 can betransferred to the loader 10 from each of the three drums 12 on asequential basis, using the above-described process.

The cover system 10 can permit a particulate substance, such as thecatalyst and/or additive 11, to be unloaded from a container, such asthe drum 12, without damaging the container due to an excessive pressuredifferential between the interior of the container and the ambientenvironment. Unloading a container while it is covered can substantiallyreduce the potential for fugitive emissions and other losses of theparticulate substance during the unloading process. Unloading acontainer in this manner can also reduce the potential for humanexposure to the particulate substance. Eliminating human exposure andfugitive emissions can be particularly beneficial, for example, inapplications where the particulate substance is toxic, caustic, orotherwise harmful to humans or the environment.

Moreover, the ability to unload a container while the particulatesubstance therein is substantially isolated from the ambient environmentcan minimize the potential for contamination of the particulatesubstance. The use of the cover system 10 can thus be especiallybeneficial, for example, in applications where the particulate substancepossesses hygroscopic properties. More specifically, the cover system10, by isolating the particulate substance from the ambient environment,can minimize or substantially eliminate the absorption of water by ahygroscopic material during the unloading process.

By “hygroscopic,” it is meant having the property of absorbingatmospheric moisture. Hygroscopic materials include, but are not limitedto, food products, pharmaceuticals and industrial chemicals, as well ascatalyst and/or additives, e.g., FCC catalysts and/or additives.

The ability of the cover system 10 to substantially isolate aparticulate substance within a container from the ambient environmentcan also be beneficial, for example, in applications where theparticulate substance possesses pyrophoric, i.e., spark or flameinducing, properties. It should be noted that the cover system 10 can beused in connection with particulate substances other than pyrophoricand/or hygroscopic materials.

The use of the cover system 10 can permit the particulate substance tobe transferred directly to its point of use, e.g., the loader 102,without a need to transfer the particulate substance to an intermediatevessel from which the particulate substance is subsequently betransferred.

The cover system 10 is believed to be particularly well suited for usewith relatively small, mobile loaders, such as the loader 102, as thesetypes of loaders are well suited to draw particulate matter from storagedrums rather than large storage hoppers or rail cars. Moreover, the useof the cover system 10 can permit one or more of the drums 12 to beunloaded at a site remote from the loader 102, in relatively quicksuccession. It should be noted that the cover system is not limited touse with small, mobile loaders; the cover system 10 can be used inconnection with relatively large and/or stationary loaders.

The foregoing description is provided for the purpose of explanation andis not to be construed as limiting the invention. Although the inventionhas been described with reference to preferred embodiments or preferredmethods, it is understood that the words which have been used herein arewords of description and illustration, rather than words of limitation.Furthermore, although the invention has been described herein withreference to particular structure, methods, and embodiments, theinvention is not intended to be limited to the particulars disclosedherein, as the invention extends to all structures, methods and usesthat are within the scope of the appended claims. Those skilled in therelevant art, having the benefit of the teachings of this specification,may effect numerous modifications to the invention as described herein,and changes may be made without departing from the scope and spirit ofthe invention as defined by the appended claims.

1. A process for transferring a particulate substance from a containerto an injection device capable of injecting the particulate substanceinto a fluid stream, comprising: installing a cover on the container,wherein the cover has a fitting mounted in a hole formed in the cover,and a wand connected to the fitting, and the wand is inserted into theparticulate substance while the cover is installed on the container; andvacuuming the particulate substance through the wand and into theinjection device.
 2. The process of claim 1, further comprising placingthe wand in fluid communication with the injection device prior tovacuuming the particulate material.
 3. The process of claim 2, whereinplacing the wand in fluid communication with the injection devicecomprises connecting the fitting to a hose or a pipe in fluidcommunication with the injection device.
 4. The process of claim 1,wherein vacuuming the particulate substance through the wand and intothe injection device comprises vacuuming the particulate substancethrough the wand and into the injection device in response to a vacuumproduced by a vacuum source of the injection device.
 5. The process ofclaim 1, wherein installing a cover on the container comprises placingthe cover on the container and sealing an interface between the coverand the container.
 6. The process of claim 1, further comprising tiltingthe container before vacuuming the particulate substance through thewand and into the injection device.
 7. The process of claim 6, whereintilting the container before vacuuming the particulate substance throughthe wand and into the injection device comprises tilting the containerso that a central axis of the container is angled less thanapproximately ninety degrees in relation to the vertical direction. 8.The process of claim 7, wherein tilting the container before vacuumingthe particulate substance through the wand and into the injection devicecomprises tilting the container so that the central axis of thecontainer is angled between approximately twenty to approximately sixtydegrees in relation to the vertical direction.
 9. The process of claim6, wherein tilting the container before vacuuming the particulatesubstance through the wand and into the injection device comprisesplacing the container on a cradle that supports the container in atilted orientation.